cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-1 of 1 results.

A385488 Decimal expansion of the surface area of a gyroelongated pentagonal birotunda with unit edge.

Original entry on oeis.org

3, 7, 9, 6, 6, 2, 3, 6, 8, 8, 2, 7, 5, 6, 3, 7, 6, 0, 0, 8, 3, 8, 2, 6, 0, 7, 1, 4, 3, 7, 2, 2, 0, 3, 8, 8, 6, 2, 3, 1, 6, 5, 4, 2, 5, 7, 8, 2, 2, 6, 1, 8, 6, 2, 3, 1, 0, 4, 3, 2, 0, 6, 2, 7, 8, 8, 0, 5, 7, 5, 8, 0, 7, 5, 5, 9, 5, 5, 9, 5, 1, 4, 6, 8, 0, 0, 7, 5, 6, 7
Offset: 2

Views

Author

Paolo Xausa, Jun 30 2025

Keywords

Comments

The gyroelongated pentagonal birotunda is Johnson solid J_48.

Examples

			37.966236882756376008382607143722038862316542578226...
		

Crossrefs

Cf. A385264 (volume).

Programs

  • Mathematica
    First[RealDigits[10*Sqrt[3] + 3*Sqrt[25 + 10*Sqrt[5]], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["J48", "SurfaceArea"], 10, 100]]

Formula

Equals 10*sqrt(3) + 3*sqrt(25 + 10*sqrt(5)) = 10*A002194 + 3*sqrt(25 + 10*A002163).
Equals the largest root of x^8 - 2100*x^6 + 1032750*x^4 - 121162500*x^2 + 1216265625.
Showing 1-1 of 1 results.